1. Field of the Invention
The present invention relates to technology for non-volatile storage.
2. Description of the Related Art
One example of non-volatile memory uses variable resistance memory elements that may be set to either low or high resistance states, and can remain in that state until subsequently re-set to the initial condition. The variable resistance memory elements are individually connected between two orthogonally extending conductors (typically bit and word lines) where they cross each other in a two-dimensional array. The state of such a memory element is typically changed by proper voltages being placed on the intersecting conductors. Since these voltages are necessarily also applied to a large number of other unselected memory elements because they are connected along the same conductors as the selected memory elements being programmed or read, diodes are commonly connected in series with the variable resistive elements in order to reduce leakage currents that can flow through them. The desire to perform data reading and programming operations with a large number of memory elements in parallel results in reading or programming voltages being applied to a very large number of other memory elements. An example of an array of variable resistive elements and associated diodes is given in U.S. Patent Application Publication No. US 2009/0001344.